Cartridge belt link guide



July 13, 1948. R. JJMaCFARLANE ETAL 2,444,936

CARTRIDGE BELT LINK GUIDE Filed May 2, 1946 Rich ar cf J MacFar'lan aHar [11d Kersh aw way.

longitudinal axis thereof.

Patented July 13, 1948 UNITED STATES TENT FFi C E CARTRIDGE BELT LINKGUIDE Richard J. MacFarlane, Springfield, Mass, and Harold E. Kershaw,Hartford, Conn.

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) 7 Claims.

The invention described herein may be manufactured and usedby or for theGovernment for governmental purposes, without the payment to us of anyroyalty thereon.

This invention relates to improvements in feeding ammunition throughmachine guns and is directed more particularly to a link guide for suchmachine guns which use a disintegratinglink type ammunition belt.

It has occasionally been found in the manuiacture of cartridges and inthe loading of the same into belts that occasionally a bullet is forcedinto its cartridge case beyond the proper seating depth resulting in anoverall cartridge length shorter than the minimum prescribed therefor.Cartridges of this nature are commonly referred to as short rounds andwill invariably cause a failure to feed when loaded into a Browning typemachine gun because the extractor will merely strike the base of theshort round and push such forward until the bullet thereof strikes theconventional bunter plug at the front or the feed- In addition to thisfailure to feed, possible injury to the nose of the bullet may occur asthe result of striking the hunter plug and in the case of frangibleammunition used for training purposes, complete shattering of suchbullets will, no doubt, take place.

Machine guns of the Browning type are normally adapted to use adisintegrating type of metallic belt link. Such links comprise aforward- 1y extending double 100p and a rearwardly extending singleloop. The single loop of one link is inserted between the double loop ofan adjacent link and a cartridge is forced through the opening definedby coupling the links in such fashion. A plurality Of cartridges andlinks assembled thus form a cartridge belt in whatever length may bedesired. A conventional belt filling machine is normally used to loadcartridges into link belt form and by the nature of its operationinsures that all links are uniformly positioned on the cartridges withrespect to the The cartridges of course are presumably identical inshape and length.

It can thus be readily seen that if the links are uniformly guidedthrough the feed channel of a machine gun, each cartridge held by the.links will therefore be longitudinally positioned for proper extractionfrom the belt regardless of the overall length of the cartridge.

This locating feature of linked cartridges has heretofore beenrecognized in the construction of devices adapted to align cartridges inthe feedway of a machine gun for proper extraction from the cartridgebelt. However, such previous devices have been located in the gun abovethe cartridge belt and have therefore been subject to battering andscufiiing as the belt is fed through the gun. But the device of thisinvention is so constructed as tolie along the floor of the transversefeed channel underneath the cartridge belt thereby offering a minimum ofresistance to the feeding of such belt and decreasing the possibility ofexcess wear and breakage. In addition, positioning the device of thisinvention in the manner described positively assures no interferencewith the opening and closing of the gun cover, as occasionally occurredin other short round devices fastened to the cover or positioned abovethe ammunition belt.

Little or no attention has previously been paid to guiding the links outof the gun after extraction of a cartridge has taken place. In machineguns of the type with which we are here concerned, there is a shortinterval of time in which a link lies free in the feedway of the gun. Onrecoil of the gun, a cartridge is fully extracted from the links at aninstant of time which is a little more than half of that required forcom pletion of the rearward travel of the recoiling parts of the gun. Itis then that the previously mentioned coupling of the links is brokenand the links from which the cartridge has been extracted is free of thebelt. After counterrecoil of the gun has begun, the next round in thebelt is moved up to the extracting position in the feedway and by doingso pushes the free link along the feedway out of the gun. But during theshort interval of time in which the link is free, it is subject tomovement as a result or the vibration of the gun and in particular theshock of the recoiling parts striking the buffer at the end of therecoil stroke. The free link therefore tends to jump and twist in thefeedway before such time as it is pushed out by the feeding of the nextcartridge. As a result, such link may interfere with the feedingmovement of the belt by jamming against the closed cover of the gunthereby causing a stoppage in the firing of the g n.

Modern practice, particularly with respect to machine guns intended forairplane use, requires that the feed mechanism and associated parts ofthe gun be adjustable so that the direction of feeding may be readilyreversed without the addition or substitution of any parts. The guideunit of the present invention is symmetrical in shape and is thereforeadapted to function equal- 1y well regardless of the direction offeeding of the gun.

Accordingly it is an object of this invention to provide a link guidefor a machine gun whereby both the cartridges and links comprising anammunition belt will be properly guided during the feeding operation ofthe gun.

It is a further object of this invention to provide an improved devicefor correctly positioning cartridges for positive extraction from anammunition belt by using the forward edges of the foremost link as alocating point.

It is another object of this invention to provide a device for guidinglinks out of the feedway of a machine gun so as to prevent link jamstherein.

It is still another object of this invention to provide a link guidewhich functions equally well in a machine gun regardless of thedirection in which the belt is fed therethrough.

It is a particular object of this invention to provide a link guide fora machine gun such as disclosed in U. S. Patent No. 1,628,226 to John M.Browning.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of thepreferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a perspective view of a portion of a machine gun illustratingthe link guide applied thereto;

Fig. 2 is a sectional detail view taken on a vertical plane through line22 in Figure 1 showin a cartridge in extracting position on the linkguide of the present invention;

Fig. 3 is a section taken along line 33 in Fig. 2;

Fig. 4 is a perspective view of the link guide; and,

Fig. 5 is a perspective view showing a fragment of a cartridge belt.

The operation of the feed mechanism of the Browning type machine gunherein mentioned is fully described in Patent No. 1,628,226 to John M.Browning. For purposes of explaining the advantages and features of thepresent invention, reference will be made to details of such feedmechanism, but it should be understood that this invention is alsoapplicable to any machine gun using a metallic disintegrating-link typeammunition belt in the manner similar to that disclosed in the Browningpatent.

The machine gun shown in Fig. 1 includes a receiver casing 2 having atransverse feed channel 4 for the passage of a linked belt 6 comprisingcartridges 3 and links 9. A cover H is pivoted to casing 2 as shown atl3 and is in the open position in Fig. 1. An axially movable breech boltII] is provided with a pivotally mounted extractor |2 for withdrawingcartridges 8 from belt 6. Bolt l9 serves in the well known manner tocause actuation of a feed slide 3 which moves belt 3 through feedchannel 4 by means of a pawl 5. Slide 3 is located in cover II as shown.

On each side of the gun there is provided a bracket I 2 secured toreceiver casing 2 so as to form the end portions of feed channel 4.Ass0- ciated with the bracket Id at the entrance end of feed channel 4is a belt holding pawl (not shown) designed to engage successivecartridges to prevent any possible backward movement of belt 6. On theopposite end of the feed channel 4 the bracket It is provided with afront cartridge stop l8, a link stripper 29 designed to preventexcessive twisting of belt 6 when a cartridge is extracted therefrom,and a rear cartridge stop 2|. Stops I8 and 2| and link stripper 20 limitthe feeding movement of cartridge belt 6 and are held in place by alongitudinal retaining pin l6 extending through the apertures in bracketl4. Another retaining pin I6 is provided in the bracket I 4 at theentrance end of feed channel 4. It will be understood that while parts3, I8, 20, and 2| are in the relationship shown when the gun is intendedfor left hand feeding, these same conventional parts are interchangeableto opposite sides of the gun when it is desired to feed the belt fromthe right hand side of the gun.

Shown in Fig. 5 is a fragment of cartridge belt 6 including a cartridge8 and links 9 in the relationship previously mentioned. Cartridge 8 isprovided with an annular groove near the rear end which defines ashoulder 1 adapted to be engaged by extractor l 2.

The link guide 25 of this invention is shown particularly well in Fig, 4and consists essentially of a strip of spring-like metal having anelongated body portion 39 and opposite end portions which are bentdownwardly and then inwardly towards one another so as to defineU-shaped curves 32 with open sides facing one another. Body portion 30is formed so that its central rear portion 33 is curved convexly toproject rearwardly of the opposite U-shaped end portions 32. The centralrear portion 33 is also flared upwardly so as to be in a higherhorizontal plane than the rest of body portion 39. The entire bodyportion 30 is also slightly convexly curved so as to be in a highervertical plane than the opposite U- shaped ends 32.

To assemble the link guide 25 to the gun, one U-shaped end 32 is placedso as to engage retaining pin I6 on one side of feed channel 4 and theother retaining pin IS in the bracket at the entrance end of feedchannel 4 is partially withdrawn and then reinserted to engage theopposite U-shaped end portion 32 of the link guide. It should beunderstood that it is immaterial which retaining pin first engages aU-shaped end portion since the link guide is symmetrical and whenassembled to the gun is adapted to function equally well in whicheverdirection feeding of the belt takes place. In either case, the linkguide 25 overlies the floor of feed channel 4 with the upraised centralportion 33 facing the bolt IO and extractor l2 of the gun.

As linked belt 6 is moved through feed channel 4 by feed slide 3, theforemost cartridge 8 presses down on the upraised central portion 33thereby insuring that the free edge thereof positively abuts the forwardedge of the foremost cartridge link 9. Thus cartridge 8 is properlylongitudinally positioned in the feedway to permit engagement of theextractor l2 with the annular shoulder 1. Regardless of the overalllength of car tridge 8, such cartridge is properly located due to theuniform positioning of the cartridge links 9 thereon.

As cartridge 3 is withdrawn from belt 6 by extractor l2, the foremostlink 9 is set free from the remainder of belt 6 as previously described.But when the link guide 25 of this invention is present in the gun, theforemost link 9 is kept from twisting or turning in feed channel 4 bythe rear edge of body portion 30 lying in front of the forward edge ofsuch link. Furthermore when cartridge 8 has been withdrawn from belt 6,the pressure on central portion 33 is relieved allowing the link guide25 to return to its original bowed shape. Thus the rear edge of bodyportion 3% rises even higher in front of the link 9 and prevents unduetwisting or turning thereof with the consequent jamming in feed channelt against cover l G. And as the next successive cartridge is fed intochambering position, it pushes free link 9 out of feed channel l. Properguidance of free link Si is insured by the remainder of the rear edge ofbody portion 36.

Such guiding effect is particularly true in the case of the lastcartridge in the belt. In such event there are two free links remainingafter the cartridge has been extracted therefrom. Without the link guideto keep such links from twisting, a link jam is highly probableespecially in high speed guns.

It can thus be readily seen that not only does the rear edge of bodyportion 3i! guide the links coming out of feed channel to prevent linkjams therein, but also guides the incoming links containing cartridgesso as to properly position such cartridges for positive extraction fromthe linked belt.

It will also be appreciated that the link guide of this invention issimple to manufacture and easy to assemble and disassemble.

We claim:

1. A link guide for a disintegrating-link belt fed machine guncomprising, an elongated body portion having inwardly facing opposedU-shaped ends whereby said link guide is mounted to the gun, said bodyportion bowed so as to be elevated above the plane of said U-shapedends, said body portion having a convexly curved central rear portionupwardly inclined so as to prevent an elevated free edge in a planehigher than the remainder of said link guide.

2. In a belt fed machine gun having a transverse feed channel adapted toreceive a linked belt of cartridges, a link guide mounted on the feedwayadjacent the forward side thereof, said link guide comprising anelongated body adapted to lie beneath the linked belt of cartridges, andU-shaped ends facing inwardly and oppositely for mounting said linkguide to the gun, said body having a convexly curved central rearportion upwardly inclined so as to present an elevated free edge adaptedto lie in front of the foremost link in the belt of cartridges.

3. In a belt fed machine gun having a transverse feed channelterminating in bracket ends, each apertured to receive a longitudinalpin, and a belt of linked cartridges disposed in the feed channel, aunitary member comprising, an elongated body adapted to lie along thefeed channel beneath the belt of cartridges, and U-shaped ends facinginwardly and oppositely for engagement with the longitudinal pinswhereby said unitary member is mounted to the gun, said body having aconvexly curved central rear portion inclined so as to present anelevated free edge, all adapted and arranged whereby said elevated freeedge bears against the forward edge of the link surrounding the foremostcartridge to properly position such cartridge in the feed channel forextraction from the belt.

4. A device as described in claim 3 but wherein said unitary member isbowed so as to provide resiliency thereto when depressed by the belt ofcartridges, said U-shaped ends therefore slidably engaging thelongitudinal pins.

5. In a belt fed machine gun having a transverse feed channel adapted toreceive a linked belt of cartridges, means for feeding the linked beltthrough the feed channel, and means for extracting cartridges from thelinked belt, the improvement comprising a resilient unitary memberhaving an elongated body adapted to lie along the transverse feedchannel beneath the linked belt of cartridges, said elongated bodyhaving the opposite ends thereof bent downwardly and inwardly to formU-shaped passages adapted for mounting said unitary member to the gun,all adapted and arranged whereby the links containing cartridges areproperly guided into the feed channel of the gun during the feedingoperation thereof and whereby the links freed from the belt whenextraction of a cartridge has taken place are properly guided out of thefeed channel to prevent link jams therein.

6. In a belt fed machine gun having a feed channel adapted to receive alinked belt of cartridges, the links uniformly positioned on thecartridges, means for feeding the linked belt of cartridges through thefeed channel, and means for extracting the cartridge from the linkedbelt, the improvement comprising a resilient unitary member having anelongated body adapted to lie along the transverse feed channel beneaththe linked belt of cartridges, said elongated body having the oppositeend portions thereof bent downwardly and inwardly to form U-shapedpassages adapted for mounting said unitary member to the gun, saidelongated body having a rear central portion convexly curved andinclined upwardly so as to present a free edge elevated over theremainder of said body, all adapted and arranged whereby said elevatedfree edge longitudinally positions each cartridge in the feed channelfor extraction from the linked belt regardless of the overall length ofthe cartridge and whereby the remainder of said body guides the linksthrough the feedway so as to prevent link jams therein.

'7. In a belt fed machine gun having a transverse feed channel adaptedto receive a. linked belt of cartridges, and means for feeding thelinked belt across the feed channel in either a left hand or right handdirection, the improvement comprising a symmetrical resilient unitarymember having an elongated body adapted to lie along the transverse feedchannel beneath the linked belt of cartridges, said elongated bodyhaving the opposite ends thereof bent downwardly and inwardly to formU-shaped passages adapted for mounting said unitary member to the gun,said elongated body having a rear central portion convexly curved andinclined upwardly so as to present a free edge elevated over theremainder of said body, all adapted and arranged whereby said elevatedfree edge longitudinally positions each cartridge in the feed channelfor proper extraction from the linked belt and whereby the remainder ofsaid body guides the links through the feed channel so as to preventlink jams therein, both features unaffected by the direction in whichthe linked belt may be fed through the feedway.

RICHARD J. MAcFARLANE HAROLD E. KERSI-IAW.

